The field of the invention is cosmetic applicators and the invention relates more particularly to cosmetic pencils for dispensing a soft cosmetic mass such as an eyeliner crayon.
A cosmetic pencil of the general type disclosed herein is shown in applicant's U.S. Pat No. 4,696,594. In this device a push head cylinder 27 is placed within the sheath member prior to filling with a cosmetic mass and the push rod 22 contacts its head. The push rod is advanced by an off-centered disk. While this construction has been very satisfactory, it does require that the sheath be filled from the front and it is advantageous that it be filled from the rear. It is also advantageous that there be some method of retracting the cosmetic mass when it is not in use. It is further advantageous that the push rod be assembled without having to thread it in from the bottom of the sheath portion of the applicator.
Several cosmetic applicators utilize a threaded push rod which advances outwardly from a barrel. One such device is shown in U.S. Pat No. 2,563,943. Another design is shown in U.S. Pat No. 3,219,044. A piston is used in U.S. Pat No. 3,468,612 to push a liquid cosmetic mass outwardly from a cartridge. U.S. Pat No. 2,274,311 shows a push rod within a barrel which is used to advance a rectangular lead or crayon. U.S. Pat No. 3,209,730 shows an automatic pencil which utilizes a threaded end with an elongated aperature 64. The purpose of this aperature as shown best in FIG. 4 of the drawings is to permit a clutch action wherein the threaded end can move outwardly as shown in FIG. 4 and permit the turning of feed screw 16 even though there is no advance of crayon 25.